Sunday 20 June 2010 16.33 EDT
First published on Sunday 20 June 2010 16.33 EDT

Unite, the trade union representing British Airways cabin crew, is expected to launch a third round of its industrial dispute tomorrow by notifying the airline of a fresh ballot of 11,000 members.

Unite, Britain's largest trade union, has completed preparations for the vote and could send notice of it to BA as soon as tomorrow, which would mean voting begins in seven days' time. If BA's flight attendants vote for strike action for the third time in seven months, it could begin as soon as 3 August, hitting the peak summer holiday season.

In a recent letter to cabin crew, Tony Woodley and Derek Simpson, the joint general secretaries of Unite, outlined three areas of dispute: using volunteer air stewards, depriving strikers who joined walkouts in March of their concessionary travel, and "vindictive" disciplinary action taken against at least 70 flight attendants since the dispute began.

"It has become apparent that the company's continued refusal to reinstate staff travel concessions for striking members and its vindictive disciplinary measures against Unite members raises new items of dispute," said Woodley and Simpson.

Unite is serving notification of a ballot after renewed attempts by the Acas conciliation service to forge a peace deal foundered again last week. Unite believes it is close to securing a deal that will cut cabin crew costs, but is demanding the full reinstatement of the staff travel scheme for strikers as part of any agreement.

BA has made some concessions on the issue on the concessionary travel ban, but it is adamant that it will make no more, which Unite believes is tantamount to punishing staff for exercising their right to strike. A spokesman for BA said it strongly denied victimising crew, and the company was open to the prospect of further discussions.

A dispute which began last year over BA's unilateral decision to cut staffing levels on flights has now become a defining battle over Unite's power within BA. It represents around three-quarters of the airline's 38,000 staff. Industrial relations experts have warned that failure to secure an acceptable compromise in the airline's worst ever dispute will damage its stance among members.

The latest ballot will test the continuing resolve of cabin crew, who have voted in favour of industrial action by solid majorities of 92% and 81% in two polls since December last year.

However, BA believes it has tempered willingness to strike by the threat to withdraw travel perks and by running a robust contingency schedule during 22 days for strikes during March, May and June.

Unite argues that the strikes have been well supported, with at least 3,300 crew joining the March walkouts, which the union argued was a substantial proportion of those rostered to work.

However, sources state that BA is planning to take strenuous measures for any fresh round of strikes .Willie Walsh, BA chief executive, said last week that he expected to operate 100% of BA's long-haul schedule during any next wave of strike action and effectively lock out Unite and its two cabin crew branches: Bassa and Cabin Crew 89.

BA is already planning to build a corps of auxiliary flight attendants from its no-cabin crew workforce – amid complaints from Unite that volunteers are still staffing flights after strike are over.

However, one senior BA pilot has warned that any company win would be a pyrrhic victory if the airline did not act to repair the damage it had done to internal morale. Writing for the Guardian this month, the pilot said that the dispute had created "unsustainable" working conditions on flights, as he called on both sides to end the row.

"Having recently returned from a trip during the strike, what ordinary passengers can't see is the fear, intimidation and unsustainable conditions endured by those who are working," said the pilot.